Tv antenna array



1955 J. R. WINEGARD T. v. ANTENNA'ARRAY 2 Sheet-Sheet 1 Filed July 26,1954 INVEN TOR. tic W12 R; (A/megar-"zf 1955 J. R. WINEGARD T. v.ANTENNA ARRAY 2 Sheets-Sheet'Z Filed July 26, 1954 INVENTOR. V 4 ,Qwmeqrd W i/l United States Patent Ofiice 2,700,105 PatentedJan. 18, 1.955

TV ANTENNA ARRAY- John Robert Winegard, Burlington, Iowa,. assignor. toWinegard Company, Burlington", Iowa, a. corporation ofIowa ApplicationJuly 26, 1954, Serial No. 445,670

9 Claims. (Cl. 250-63251) My invention relates to animproved antennafor'television reception.

Antennas for use in television-reception musthave a wide bandcharacteristic giving good response over both the. low'frequency (54'88megacycles) television-band and the high frequency (174216 megacycles)television band. In addition, such antennas-particularly those used inlocations remotefrom television-transmitting stationsmust have a highresponse or gain in order-that the relatively weak signals fromthetransmitter may be effectively received.

In accordance with the disclosure of the present application, theseobjectives are achieved in a structure which utilizes a drivenelementin-conjunction with a coplanar director array located in front of thiselement. The director array consistsof dipoles approximately-onehalfwave-in length at a'f'requency inthe high frequency band andconnectedtogether by a-folded transmission line. The latter acts as aninductance in the:low frequency'band to cause the dipole to act'asasimpledirector in the low frequency-bandoflesszthanone-halfwavein'length. These dipoles arespacedfromzthezdriven di pole elements andfrom each' other and are coplanar with the-driven element. In additionto: these dipoledirectors, theantenna includes-a series of. unitarydirectors located in parallel, aligned, coplanar relationship with thedriven elements-and'withthe:dipole?'directors; These unitary directorsare located approximately mid way between the dipole directors andl atlike distances in front of the front director andfimbackof the reardi-zrector. Each of the unitary'directorsis approximately the same length asone arm: of'the dipolezdiiectorsi'and resonates as aone-*halfwaveunitata frequencysome what below the lowfrequencyendof'ltheshigh frequency band.

It is therefore a general objectofrthe presentzinvention to: provide animproved antenna: suitabler fOIi television reception.

A further object of the present iIIVCDfiOHZiSZIOrPIQVidC an improvedantenna:suitableifor"televisionzreception and characterized by high:sensitivity extending over the; full television frequency range of524-88? 'megacycles and 17 4 -216 megacycles;

Further it is' anobject of" theipresent invention to-rprovide an antennaof the above type utilizing-:an-inline construction; having. low wind.resistance; having; low cost; having minimum weight;andfhavingamacximumdegree of simplicity and reliability.

Additionally; it is :an object of the'present: invention to provide animproved director system for a television. an= tenna and'eifective' overboth the 48'8 megacycleband and the 174-216 .rnegacycle band.

The novel-features which I believe'to be characteristic of my inventionare set-forth with particularity, in the appended claims. My inventionitself',.however,.bothi as to its organization and method v ofoperation,.together with-furtherobjects and advantages thereof,willbestbe understood by reference-to the following description taken inconnection with the accompanying drawing in which:

Figure 1 is a view in perspective of 'a'tel'evisionantenna constructedin accordance withth'e present invention.

Figure 2 is an enlarged'fragmentary top plan'viewof the support postandadjacent portions'of the antenna structure;

Figure 3 is a view-stillfurther enlargediand'showing the I central;portions of a :dipole "director and the adjacent portionsof the supportbar;

Figure 4'is a view in perspective ofanother television antenna havingdirector elements constructed inaccordance with the present invention;and,

Figure 5 is a view in perspective of' still another antenna utilizingthe director elements of the present invention;

Referring nowto thew drawing, the antenna; is supported by a mounting.mast M which extends invertical direction and'is supportedby suitablemeans-(not shown). At thetop ofthe.mastM,.a horizontal mounting bar-'10is -affixed by-any suitable means. In the structure shown, the bar 10 isheld in place by the U'-boat 12 which is received in the bar 10 and isdrawn' tight by suitable nuts 12a,'.Figure 2, to anchor themounting bar10rigidly in place. As shown in the figures, the'various antennaelements are affixed to and supported by the bar 10;

The front driven element is shown generally at 14. This-element consistsof a forwarddipole portiondefined by arms.14'a*and a rear unitaryportion defined by'the continuous bar 14b. As shown, the dipole arms 14aare connected to=theunitany bar'14b by'the rearwardly extending arms1'4'c, each of whichis connected to the di pole arm 1'4'a'atapproximately the mid-point of its-length and extends' rearwardly indirection parallel to-the bar 10.v The'rear unitary bar14b isafiixed'to-the'support-bar lflbya saddle bracket 14d which embraces bar10 and forms a partially cylindrical seatfor bar 14b. Thebar 14b is heldtightly against the bracket 14d andthe latter is held tightly on bar 10by bolt 14e-and.thumb.. nut. 14

The adjacent ends of' the dipole.14aare. joined by spacer 14g which'isofinsulating material, such as Bakelite and has terminal posts 14k toreceive theendsofthe open transmissionline 16 which arereceived in the.ter.- minal posts and are drawn to tight seating relation bytheterminal. posts. This transmission line is held adjacent the bindingposts 14h by the arm 16a which is afli'xed at one end'to the mast M andat the other end has itn insulatingsleeve 16b which receives thetransmission A similar driven element 18 is located rearwardly on bar 10in relation to the unit 14. The unit 18 is-oflike construction. usingdipole arms. 18a, a unitary bar18b extending. parallel to andin linewith the elements and a pain of connecting bars approximately midway onthe. dipole. elements and extending parallel to the support liarl'tlbetween the. dipole elements ISaancLtheunitary rear elementlSb. Thedipole elements 18a are. likewise connected attheir adjacent endstotheinsnlating spacer 18g which has binding posts 18h to. receive.theopen transmission line 20 definedby. conductorst20a and2llb which isreceived on the binding posts14h' at its front end and receives thebinding posts 18h at its rear end.

The forwardidriven element 14 is.of such.length as.to receive mostefficiently in the high frequency television band ofl74-2'l6:megacycles. In this frequency. range the transmission. line 20,including the. stub portions outboard of element 18, acts as a one-halfwave open line to present avery high impedance acrossthetra-nsmissionline 16. The rear driven element18iisof lengthitoreceive mostefiiciently in the low frequency televisionband of 54-88 megacycles. Inthis frequency range the transmission line 20 acts as a non-resonantline.

Rearwardlyof the unit 18; there-is provided a-reflector 22"whichconsistsof a unitary'bar extending parallel'to and -in'- coplanar alignedrelationship withthe'units 14 and 18. This-baris-attached to the supportbar 10'by the saddle 22a and "by the anchor bolt 22b and thumb nut 220as shown.

'Forwardly of the driven element 14 a pair of dipole directors 24 and26respectively are provided. These directors are' carried from. thesupport bar 10 by the insulating blocks 24a and 26a, respectively, eachblock being seated on the support bar 10 and held snugly thereon..by. abolt 28a. Atitstop face,,each block 24a.and 26a.has-a pair ofconductingclamp pieces 25,.Figure. 3, which areheld'snuglydown on thearmof the dipole 24 by bolts 28b which protrude beneath the. block. Eachblock 24asand 26a also'receivesthe ends of the coupling unit 24b or 26bas the case may be, thus establishing an electrical contact between thecoupling unitand the director. These coupling units are in the form offolded closed resonant lines as shown.

The arms of dipoles 24 and 26 are made slightly shorter than the arms ofdipole 14a. The resonant lines 24b and 26b are resonant, in conjunctionwith the capacitance of the adjacent parts such as bar 10, atapproximately the frequencyat which the dipoles 24 and 26 are half wavein length. Thus, at these frequencies the dipole arms are effectivelydisconnected. However, at lower frequencies the lines 24b and 26b do notfunction as resonant lines butrather as short-circuiting connectionswith some inductive effect thus causing the dipoles 24 and 26 to act asunitary directors in these frequence ranges and to appear to have asomewhat lower natural resonant frequency than their physical lengthwould indicate.

A series of three. unitary directors 29, 30, and 32 are likewise mountedon the support arm 10 in positions straddling the dipole directors 24and 26. As shown, these directors are mounted on the support bar 10 inthe same fashion as reflector 22, that is, by the use of a saddle and anappropriate mounting bolt. The directors 29, 30, and 32 areapproximately the same length as the arms of the respective dipoles 24and 26. Moreover, the directors 29, 30, and 32 are spaced from dipoles14a, 24 and 26, by approximately the same disstances so that directors29 and 30 are substantially midway between the respective dipoles anddirector 32 is about the same distance in advance of the dipole 26.

In an actual television receiving antenna constructed in accordance withthe present invention the following dimensions were used:

quency of about 180 megacycles).

6% inches. 25 inches.

/2 inches.

18 inches (to give an antiresonant frequency of about 180 megacycles).

Distance between dipole 26 and director 30 Length of director 30Distance between director 30 and dipole 24 Length of resonant line 24bDistance between dipole 24 and di rector 29 7 inches. Length of director29 25% inches. Length of dipole arms 14a 25 inches. Distance betweendirector 29 and the parallel portions of dipole arms 14a 4 inches.Length of arms 14c 4 inches. Length of bar 14b 70 inches. Length oftransmission line 20 .28 inches. Length of dipole arms 18a 38 inches.Length of bars 180 4 inches. Length of bar 18b 99 inches. Length ofreflector 22 110 inches. Distance between reflector 22 and bar 181) 24inches.

An antenna constructed in accordance with the above dimensions has beenfound to give good response over the entire television frequency rangewith an average gain of about 6 decibels over a simple dipole.

It will be observed that the antenna above described is an antennawherein all of the antenna elements lie in a common plane. This providesa desirably low wind resistance. It also makes it possible to mount theantenna parts on the common support bar 10. In addition, the antenna isof rugged construction and is simple in design, features whichcontribute to its general usefulness.

In the antenna above described it has been found possible to receive alltelevision bands without difficulty. The directional characteristics areapproximately those of a dipole with a single reflector so that theantenna displays a substantial degree of directivity without beingunduly critical.

1 The spacings between the various elements of the anlength to operateeffectively tenna of Figure 1 may be adjusted to vary the antennacharacteristics such as the impedance as seen by the transmission line16. Within reasonable limits these spacings are not critical althoughfor normal television E186 approximately the proportions of Figure l arepreerre The characteristics of the resonant elements 24b and 26b aregreatly influenced by the capacitance eflects of the adjacent parts,particularly the support arm 10 which is of metal such as aluminum. Thecapacitance resulting from this arm together with the capacitance of thehardware such as the clamps 25, causes these resonant elements toresonate at a frequency considerably lower than their length wouldindicate. This is a highly desirable feature of the structure of thepresent invention since the inductive reactance of these elements in thelow frequency band is lower than would otherwise be the case. As aconsequence of this lower inductance the units 24 and 26 effectively actas directors in the full 54-88 megacycle band. Were it not for thiseffect, the director action of these elements would be lost near thehigh frequency end of this band, and, indeed, these elements might evenact as reflectors and defeat their purpose.

The action of the directors 24 and 26, in conjunction with directors 29,30 and 32 can be regarded as that of a high band director system usingelements 29, 30 and 32 interposed on a low band director system usingelements 24 and 26. However, the action of the coupling units 24b and26b is to avoid the shielding effect otherwise associated with directors24 and 26 and to cause these directors to give some director action inthe high frequency band. At the same time, however, the coupling units24b and 26b provide a degree of inductive reactance at the low frequencyband and thus give rise to good director action in that band even thoughthe length of directors 24 and 26 would otherwise be too small at thehigh frequence end of that band.

Figure 4 shows an alternative antenna structure using a director systemconstructed in accordance with the present invention. In this system themast M carries a support bar or boom which in turn carries reflector122. Forwardly of the reflector there is provided a two band drivenelement 114 of the type de-v scribed and claimed in my copending patentapplication entitled Dual Band Antenna, Serial No. 446,010, filed July27, 1954. In brief, this driven element consists of a pair of spacedcoiinear dipole arms 114a of in the low frequency band. A pair offorward angled dipole elements 114b are mounted at the inboard ends ofdipole elements 114a by means of the connecting and supporting arms 1140and 114d. The entire unit is aflixed to the boom 110 by an insulatingsupport 114e as described more particularly in the above-identifiedapplication. Transmission line 116 is connected to the inboard ends ofthe arms 114a as shown.

The arms 114d are so positioned on the dipole arms 114b and 114a as todefinein conjunction with the outboard portions of these dipole arms-ahalf wave open circuited resonant transmission line in the highfrequency band. This reflects a very high impedance which causes theportions of arms 114a and 114b inboard of arms 114d to operatesubstantially independently of the outboard portions in the high band,thus giving rise to action similar to that of a simple half wave dipole.

The boom 110 receives director 124 forwardly of the driven element 114.This director is like director 24, Figure 1, and includes a couplingline 124b to give the dual band action described above in connectionwtih director 24. The director 129constructed like director 29, Figure1is interposed between director 124 and the driven element 114.

In operation, the two arms of director 124 are effectively disconnectedin the high frequency band and the director 129 operates as a director,while the driven element 114 operates in generally the same manner as ifit consisted only of the portions inboard the arms 1140!. In the lowband the director 124 operates as a director with the coupling 124bcontributing more inductive reactance and the arms 114a and 114b of thedriven element operate in a manner similar to a half wave dipole.

Figure'S shows still another antenna having a director systemconstructed in accordance with the present inven tion. In this antennathe boom 210 carries a pair of zrnroa' es spaced low band'an'd high"bandifol'ded"dip'oies, are -11a '?14, respectively. Transmission line.H6 ''is connected to the'dipole'218 'andthrougl1 a resonantsectionf216a'to the low band dipole 21.8. 'rhessection"2l6aacts 'as' an"open one-halfwave line at the "high tban'dto decouple the lowband'dipole -218Iin this'band, whereas the effect of the dipole 218 isnegligible'at'thelow'band.

The director 224, constructed' like 'director'24,:Figure 1,; is .located:forwardly of "the driven elements 214 and f21'81and acts primarily to,give director action "in' thelow "frequency band. The resonant coupler224a contributes indu'ctance to director 224 at "the ;low' frequencyband and electrically separates the'a'rms of director224 inithe thighfrequency band. .A second director 229 is located .forwardly of thedirector 2'24 and'is-cuttolen'gthrto act as a director in the highfrequency band.

While the present invention is particularly applicable to televisionantenna-applications, 'it is usable generally where a high :frequencyantenna must operate in two fre'quency bands, one about twice-thefrequency .of the other. One such application is that of .amateur radioantennas for use in, say,' both. the 10 meter .and 210- meter .amateurbands, eitherfor transmitting or receiving.

-Itwill be noted that the directors "24, "26, 29,'30and '32.are inparallel coplanarmelation with respectto the remaining elements ofthe-antenna. In addition, these directors are symmetrical about the boom10 andhence are aligned withieach other land with the remainingelements.

While I have shown and described a specific embodi- 'ment of the-presentinvention it will; ofxcourse,'be'-'underrstood that variousmodifications and-alternative constructions may-be madewithoutdepart-ing from its'true .spirit rand scope. In particular, it ispossible-to vary:individual :dimensions-from those shown to .accent theresponse'of rtlre antenna toparticular frequencies or to suppress suchtresponse. These adjustments can be-smade on'a cut and ttry basis toaccommodate the antenna to particular conditions or to provide acharacteristic deemed superior for general use to that of the antenna asspecifically described above. I therefore intend by the appended "aplurality of laterally spaced'pairs oflilredirector tile claims to coverall antennas falling within their true spirit and scope.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A television antenna to receive signals over a wide frequency bandcomprising in combination: a pair of coplanar parallel spaced drivenunits each having a forward dipole and a closely spaced rear unitaryelement, the dipole being connected to the unitary element by transverseconductors positioned approximately midway along each arm of the dipole;a plurality of dipole directors each having total length approximatelyone-half wave in length at a frequency near the low frequency end of theband located forwardly and in coplanar parallel relation with the drivenunits, the dipoles being spaced from each other and from the forwarddriven unit; antiresonant elements tuned to a frequency near the highfrequency end of the band connecting the adjacent ends of the arms ofthe dipole directors; and unitary directors approximately one-half wavein length at the high frequency end of the band, the last mentioneddirectors being interposed approximately midway between the adjacentdipole directors and between the forward driven element and the adjacentfirst dipole director.

2. An antenna for use in receiving signals throughout the frequencyrange of the low frequency and high frequency television bandscomprising in combination: a driven element operable to receive signalsin said bands from a predetermined direction; a plurality of coplanarparallel aligned director elements located in said direction from theantenna; each of said elements being approximately one-half wave inlength at the high frequency end of the high frequency band; a pluralityof pairs of dipole director elements in coplanar parallel alignedrelation with said first mentioned director elements, the total lengthof each of said last directors being approximately one-half wave in thelow frequency band, the pairs of dipole director elements beinginterposed substantially midway between the first mentioned directorelements; and resonant couplings connecting the adjacent ends of thedipole director elements, the couplings being resonant at frequencies inthe high frequency band and having an inductive reactance in the lowfrequency band whereby in the high frequency band 'ments in parallelcoplanar relationwi'th and interposed between the first directorelements in 'said'directio'nfto define dipoles; and coupling elementsconnecting 'the 'ad- ,ja'ce'nt ends of the "directors of'saidlastpair's, the'cou'pling elements being resonant at afrequency inthe hig'hlfrequency end .of the range whereby in thehigh'ffrequency endof the range thepairs o'fdirector elementsactfi'ndividuallyasresonanttdirectors without shielding the 'first .mentioned directorelements and ..at Ithe'lowifrequency endof therangethe pairs ofdirectors actin uriisonas resonant directors.

4. In an antenna fortelevision useto receive signals in both the high'frequencyand low (frequency television band, the improvement:comprising: a driven r element adapted to receive telcvision .signals;a unitary-director located rin-parallel-coplanar relation withthetdriven elemerit, the director being approximately.one-half wave; inlength in the high :frequency -.band; a dipole director located incoplanar {parallel aligned relation with the driven element and unitarydirector, 'thedipole -.director having total length substantially ahalf--wave -length-in .the a low frequency television bandgr-and -a resonanttrans- -mission line having a a large shunt capacitance. connecting theinboard ends of the dipole-director and-resonant tin the high frequencyband, -wherebyzintthe high frequency I hand the dipole directorlact-s asatpaiiwof-individual resonant directors without zshielding-tthe-dri-venelement or unitary director and in the low frequency band the dipoledirector acts as a unitary resonant director.

5. A director system for a two band antenna, the director systemcomprising in combination: a unitary director of length to operate as adirector in the high frequency band; and a dipole director in coplanarparallel aligned relation with the unitary director, the dipole directorconsisting of colinear dipole arms joined at their inboard ends by acoupling unit resonant in the high frequency band, the length of thedipole director being such as to give director action in the lowfrequency band in conjunction with the impedance of the coupling unit,whereby in the high frequency band the dipole director acts as a pair ofindividual resonant directors without shielding effects and in the lowfrequency band the dipole director acts as a unitary resonant director.

6. A director system for a two band antenna having a longitudinalsupport boom, the director system comprising in combination: a unitarydirector of length to operate as a director in the high frequency band,the unitary director being affixed in centered relation on the boom; anda dipole director mounted on the boom in coplanar parallel alignedrelation with the unitary director, the dipole director consisting ofdipole arms insulatingly supported in colinear relation from the boom;and a coupling unit joining the inboard ends of the dipole arms, thecoupling unit comprising a closed parallel wire transmission lineconductively attached to the inboard ends of the dipole armsrespectively, extending in parallel relation to the boom for part of itslength adjacent the dipole arms to embrace the same, and in a planenormal to the boom extending in U-shaped configuration about the boomfor the remainder of its length, the coupling unit being resonant in thehigh frequency band in conjunction with the capacitance of the boom, thelength of the dipole director being such as to give director action inthe low frequency band in conjunction with the impedance of the couplingunit.

7. An antenna for television use comprising in combination: a conductingsupport boom; a driven element mounted on the boom in centered relationand adapted to receive signals from one direction lengthwise of the boomand over a wide range of frequencies; a plurality of parallel coplanardirector elements mounted on the boom in spaced centered relation insaid direction from the driven element, said elements being resonant ata frearms to embrace the same and in a plane normal to the boomextending in U-shaped configuration about the boom for the remainder ofits length, each transmission line being resonant in the high frequencyband in conjunction with the capacitance of the boom,

each dipole being such as to give director action in the low frequencyband in conjunction with the impedance of the transmission line.

8. A television antenna to receive signals over a wide frequency bandcomprising in combination: a conductthe length of ing boom; a pair ofcoplanar parallel spaced driven units each having a forward dipole and aclosely spaced rear unitary element, the dipole being connected to theunitary element by transverse conductors positioned approximately midwayalong each arm of the dipole, each of said driven units being mounted onthe boom; a plurality of dipole directors having a pair of colinear armsinsulatingly mounted on the boom, each dipole director having a totallength of approximately one-half wave in length at a frequency near thelow frequency end of the band and located forwardly and in coplanarparallel relation with the driven units, the dipole units being spacedfrom each other and from the forward driven unit; closed parallel wiretransmission lines connected to the inboard ends of the dipoledirectors, respectively, each transmission line embracing the boom for apart of its length adjacent the dipole director and in a plane normal tothe boom extending in U-shaped configuration about the boom for theremainder of its length and being tuned to a frequency near the highfrequency end of the band to ,tively,

cause the dipole director arms to operate individually at the highfrequency end of the band and in unison at the low frequency end of theband; and unitary directors approximately one-half wave in length at thehigh frequency end of band, the last directors being interposedapproximately midway between the adjacent dipole directors and betweenthe forward driven element and the adjacent first dipole director.

9. In combination, for use in a TV antenna operable over both the54-88megacycle band and the 174-216 megacycle band: a conducting supportboom; a driven element mounted on the boom and operable to receivesignals from a predetermined direction in both of said bands; a dipoledirector comprising a pair of colinear arms insulatingly supported fromthe boom forwardly of the driven element with respect to saidpredetermined direction, the total length of the director beingapproximately one-half wave in the 54-88 megacycle band; and, a closedtransmission line connected at its ends, respecto the dipole arms, saidline straddling the boom over the part of its length adjacent the dipolearms and in a plane normal to the boom extending in U-shapedconfiguration about the boom over the remainder of its length, thetransmission line being tuned to resonate in conjunction with thecapacity of the boom in the 174-216 megacycle band to cause the dipolearms to operate as individual directors in that band.

References Cited in the file of this patent UNITED STATES PATENTS1,745,342 Yagi Jan. 28, 1930 1,934,182 Franklin Nov. 7, 1933 2,204,175Carter June 11, 1940 2,268,640 Brown Jan. 6, 1942 2,380,333 ScheldorfJuly 10, 1945 2,572,166 Lorusso Oct. 23, 1951 2,578,973 Hills Dec. 18,1951 2,688,083 Hills Aug. 31, 1954

